Although adolescence is generally recognized as a period of dramatic change, the issue of whether it is also a time of stress and disturbance is still controversial. To examine the impact of pubertal development on adolescents, data were used from a 5-year longitudinal study of white males and females. A variety of self-concept, behavioral, value, and attitudinal measures indicated that for a substantial number of those dimensions, pubertal development had no effect. Early physical development was a mixed blessing for girls in terms of opposite sex popularity and greater independence but a disadvantage in terms of dissatisfaction with their body image, lower academic success, and problem behavior. For males, early development was more of an advantage linked to higher self-esteem and a more stable self-image. The findings are generally consistent with the results from other research. (JAC)